• Fire Science and Engineering
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• v.24 no.2
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• pp.145-153
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• 2010

Korea was experienced more forest fire occurrence compared to an area. As a forest fire occurrence from man caused burning for a farming increased and was one of the main reasons of forest fire occurrence in Korea, agriculturist-was a main reason of forest fire occurrence-opinion analysis was needed for forest fire prevention from this reason. Therefore, we asked agriculturist who live in province frequently experienced a forest fire from the burning for farming to answer questions. In result, a half of the respondents have a burning experience for farming and the main reason of the burning was the clearance around farmlands. In result of survey about recognition rate of forest fire prevention policy (forest fire season, incineration inhibition within 100 m from forest, license system for burning, joint burning system by a rural community, imposing a fine for burning) was almost high except license system for the burning, In the result about analysis according to ages and provinces, the recognition rate was high in province experienced severe forest fire damage and low in below 40 years group. So, the direction of forest fire prevention policy would need to be mediated in the view of agriculturist who need to use a fire because of farming labor shortage and higher age. And a consolidated education of forest fire prevention would be needed to agriculturist who live in province experienced rarely forest fire and in below 40 years group.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.3
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• pp.179-190
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• 1992

This study was carried out to characterize sources of atmospheric total suspended particulates (TSP) in urban and sub--urban areas of metropolitan taegu. The sources were tentatively identified by a multivariate technique, i.e. principal component analysis (PCA), and the source contributions to the atmospheric concentrations of TSP were further estimated by stepwise multiple regression analysis. A total of 5 sources was identified in the urban area of Taegu (soil dust resuspension, fuel combustion, secondary aerosol, traffic related aerosol, and refuge burning), while 4 sources were found to be significant in the sub--urban area as following: fuel combustion/secondary aerosol, soil dust resuspension, traffic related aerosol, and wood/agricultural burning. The largest contributor to the atmospheric TSP appeared to be the soil dust resuspension in both areas. The source apportionment of the extractable organic matter (EOM) was also carried out for the Taegu data. The EOM was determined with respect to the solvent polarity, i.e. cyclohexane (non-polar), dichloromethane (semi--polar), and acetone (polar). In addition, the source profiles for the TSP in Taegu area were estimated using a PCA-based algorithm, and the validity was evaluated tentatively by comparing the data in the literature.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.12
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• pp.1108-1114
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• 2007

The effect of oxidizer injection angle on the combustion characteristics of end-burning hybrid combustor is numerically investigated. Besides the previously studied parameter(injector arrangement, port diameter and O/F ratio), three different injection angle are considered: parallel angle to fuel surface(Case 1), +30 degree inclined angle toward the fuel(Case 2) and 30 degree inclined angle toward the nozzle(Case 3). It is found that Case 2 has the best mixing pattern in the upstream area but has the worst combustion efficiency since non negligible amount of unburned fuel is expelled from the nozzle. In contrast, though Case 1 and Case 3 showed relatively low mixing effect than the Case 2, they had high combustion efficiency. The comparison of numerical results between Case 1 and Case 3 demonstrate that no major difference is encountered, however, Case 1 is expected to have the best combustion efficiency due to the low residence time of the Case 3 injector which heads toward the nozzle.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.3
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• pp.251-260
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• 2014

Biomass burning is one of the significant emission source of PM and CO, but a few studies are reported in Korea. Air pollutants emission from biomass burning such as wood stove and boiler, and wood-pellet stove and boiler were estimated in this study. Activity levels related to biomass burning such as fuel types, amount of fuel loading, and location and temporal variation were investigated by field survey over Korea. Fuel loadings were 14.9 kg/day for wood stove, 31.3 kg/day for wood boiler, 12.8 kg/day for wood-pellet stove, 32.5 kg/day for wood-pellet boiler during the season of active use. These were mostly burned in winter season from october to april of next year. Estimated annual emissions from wood stove & boiler were CO 76,677, $NO_x$ 710, $SO_x$ 70, VOC 20,941, TSP 6,605, PM10 2,921, PM2.5 1,851, and NH3 7 ton/yr, respectively. Emissions from wood-pellet stove and boiler were CO 32,798, $NO_x$ 1,830, $SO_x$ 25, VOCs 5,673, TSP 629, PM10 457, PM2.5 344, and $NH_3$ 2 ton/yr, respectively. When the emission estimates are compared with total emissions of the national emission inventory (CAPSS: Clean Air Policy Support System), Those occupy 12.5%, 2.8% of total national emission for CO and PM10, respectively. These results show wood and wood-pellet burning appliances were one of the major source of air pollution in Korea. In future, these types of heaters need to be regulated to reduce air pollution, especially in suburb area.

• Journal of Forest and Environmental Science
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• v.33 no.3
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• pp.172-186
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• 2017

The effects of application of fuel-reduction treatment in wildfire management has not been tested in dry forests of Ghana. Therefore, the short-term ecological effects of prescribed burning and hand thinning treatments followed by experimental wildfire were investigated in degraded forests and Tectona grandis forest plantations in two forest reserves of different levels of dryness in Ghana. The results showed that more trees were killed in prescribed burning (average of 41% in degraded forest and 18% in plantations) than hand thinning (7.2% in degraded forests and 8% in plantation). More tree seedlings were also killed in prescribed burning (72%) than hand thinning (47%). The mortality of trees and seedlings were greater in Worobong South forest, a less dry forest reserve than the Afram Headwaters forest, a drier forest reserve. Fuel treatment especially prescribed burning compared to the control reduced wildfire effects on forest canopy particularly in the less dry forest and tree mortality especially in the drier forest. Prescribed burning temporarily increased pH, exchangeable potassium (52%) and available phosphorus (82%) in the surface soils of the entire plots. The two fuel treatment methods did not have much influence on basal area, organic matter and total nitrogen. Nevertheless, they were able to reduce the adverse wildfire effects on soil pH, exchangeable potassium, available phosphorus, organic matter and total nitrogen concentrations. Fuel treatments therefore have potential application in dry forest management in Ghana due to their ability to retain important forest ecological traits after a wildfire incidence.

• Journal of Oral Medicine and Pain
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• v.42 no.4
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• pp.116-124
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• 2017

Purpose: Burning mouth syndrome (BMS) is a disabling pain that mostly occurs in elderly women, but rarely in men. It is characterized by an unremitting oral burning sensation and pain without detectable oral mucosal changes. We investigated the clinical and hematologic features of middle-aged men with BMS, and compared the results to those of men with oral mucositis. Methods: Five men with BMS ($48.60{\pm}6.19years$) and five age-matched controls with oral mucositis ($49.80{\pm}15.26years$) underwent clinical and psychological evaluations and blood tests. Psychological status was evaluated using the Symptom Checklist-90-Revised. Cortisol, estradiol, progesterone, testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), adrenocorticotropic hormone (ACTH), and antidiuretic hormone (ADH) levels and erythrocyte sedimentation rate (ESR) were determined from the blood samples. Results: ADH level was significantly lower in men with BMS than in the controls. ADH levels correlated with testosterone (p<0.01), and ACTH levels strongly correlated with ESR (p<0.05). Progesterone level positively correlated with FSH and LH levels. Pain intensity on a visual analogue scale correlated with estradiol level only in men with BMS. Among psychological factors, the obsessive-compulsive disorder, interpersonal-sensitivity, and anxiety scores were higher in men with BMS than in the controls (p<0.05). However, no correlations were observed between the psychological and hematologic factors in both groups. The BMS symptoms presented only on the tongue, with the lateral border being the most prevalent area. Conclusions: Men with BMS may experience dysregulated endocrinologic or psychoneuroendocrinologic interactions, which might affect oral BMS symptoms, aggravating the severity of the burning sensation.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.4
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• pp.21-27
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• 2022

In this paper, the combustion characteristics of solid propellant embedded with metal wires were analyzed by the ground tests of motors. The propellant grains were made of thermoplastic propellants with Al and Cu as metal wires for the enhancement of burning area and designed with cone shape for better ignition. These metals were used to confirm the enhancement of burning rate on thermal diffusivity properties. The internal ballistics analysis and ground test were performed to investigate the effect of burning rate for each metal wire. We obtained the results of burning rate on a difference of thermal diffusivity of each metal wire with well-made propellant grains.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1087-1091
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• 2006

This paper describes the current spatial patterns of the net primary productivity (NPP) of the terrestrial vegetation and carbon emission (C) in the world due to the burning of fossil fuels in order to clarify the amount of expansion of human activity. The C/NPP value varies spatially from almost zero to several tens of thousand times the local NPP. C/NPP is higher under the condition of extensive human activities due to a high human population density or when the local NPP is extremely low in severe climatic zones. In contrast, the low C/NPP areas are distributed mainly in sparsely populated districts, loading to a low impact of human activity. Although the area where C/NPP is less than 10% accounts for about 70% of the entire land area, one-third of these areas cannot contribute to carbon absorption because of low NPP with a shortage of climatic resources. Since more than half of the areas of the remaining areas are agricultural land and forest ecosystems with high NPP, the possible afforestation area was evaluated to be maximum of $30{\times}10^{6}\;km^{2}$; here only sequestrate carbons that correspond to 2% of the global total NPP are present. These analyses revealed that presently most of the areas where the NPP is high are those exclusively used by humans and that it is difficult for large-scale forest plantations to absorb a substantial amount of the carbon emitted annually by humans.

• Journal of Acupuncture Research
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• v.18 no.6
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• pp.93-104
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• 2001

Objective : To localize and compare the cerebral regions- activated by the the stimulation of traditional and burning acupunctures in right Hap-Kok (LI4) acupoints. Methods : Thirty-four healthy normal volunteers (19 males, 15 females, age 31${\pm}$11 years) were studies by rest/acupuncture Tc-99m HMPAO SPECT using same-dose sequential injection method using right Hap-Kok(LI4), traditional and burning acupunctures. All images were spatially normalized and the differences between rest and acupuncture activation state were statistically analyzed using SPM 96. Results : Statistical analysis of the effect by the stimulation using traditional acupuncture in right L14 showed regional cerebral perfusion increase in right inferior frontal lobe, right straight gyrus, left anterolateral frontal lobe, left anteroinferior temporal lobe, left posterior temporal lobe, and left cerebellum. In the stimulation using burning acupuncture in right LI4, regional cerebral perfusion increased in right posterior prefrontal lobe, right precental gyrus, right postcentral gyrus, right poteroinferior temporal lobe, left precentral gyrus, left Broca's area, left anterior parietal lobe, left posterior prefrontal lobe, and left cerebellum. In right LA, diffuse perfusion increase were noted in the both inferior frontal lobe by traditional acupuncture compared to burning acupuncture. Conclusion : The results localized the cerebral areas showed the effect of the acupuncture on cerebral blood flow. The effects of traditional and burning acupunctures on cerebral blood flow were similar in right Hap-Kok (LI4) acupoints. But the effects of traditional acupunctures on cerebral blood flow are stronger than those of burning acupunctures on cerebral blood flow.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.1
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• pp.102-108
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• 2006

On the refutation demanded for a control of various toxic substances. PCBs(poly chlorinated biphenyl) has a fatal poisonous matter in the ecosystem and the environmental pollution as it Is a kind of stable chemical substance. Especially, the gross Product of PCBs is estimated at about one million tonnage all over the world. However it is kept on storing in untreated state, then has a deterioration by the Prolonged storage and a risk of overflowing. Therefore, this research examined the fundamental characteristics of combustion and emission for the target of using the IPA (iso-propyl alcohol) solution as a part of PCBs control. IPA was filled to three kinds of Vessel, i.e. Vessel I, II, and III, and then was investigated as follows combustion shape, flame temperature. mass burning velocity, and PM(Particulate matter). A radial thermometer and a C-A thermocouple measured the flame temperature, and the optical extinction method by using He-Ne laser and the filter weight method used in the PM measurement. As a result, with an increasing of L/S ratio, the flame length become shorter and the burning velocity is more rapid, but the particulate matters is higher. It is supposed that the air flow rate is high on Vessel. and then the combustion is Promoted in the surface area of the upstream zone. The future works plan to investigate the characteristics with an using of the mixing of IPA and PCBs